In robot-assisted bone milling surgery, the generation of a large amount of heat can easily lead to thermal necrosis. The irrigation fluid is commonly used to reduce the milling temperature. However, traditional research on bone milling temperature does not consider the influence of irrigation fluid. To address this, this study proposes a bone milling temperature model that comprehensively considers the effect of irrigation fluid. First, based on the finite element method, a temperature field model of cortical bone milling with a ball-end milling cutter is formulated. Then, the convective heat transfer coefficient of the irrigation fluid at different flow rates is calibrated using the point heat source temperature field theory. The results indicate that, at flow rates of 31. 6, 43. 3 and 65 μm 3 / s, the convective heat transfer coefficients are 400, 800 and 1 100 W/ ( m 2·℃ ), respectively. Finally, response surface methodology is utilized to analyze the effects of various milling parameters on the maximum milling temperature. The analysis shows that milling depth has the most significant impact on the maximum temperature, followed by irrigation fluid flow rate, feed speed, and milling angle. This temperature model and the accompanying analysis provide valuable references for selecting preoperative milling parameters and help reduce the risk of thermal necrosis during bone milling. Keywords:bone milling temperature; finite element meth